Valve assembly



June 26, 1951 T. R. THOREN ET AL 2,558,161

VAUE ASSEMBLY 32 73 519 ffii.; 72%

m' i Z 24 ,P /I i Z- 27 4Z j I l 2 34 ZL 222222175175 Meadows E 'Tare/PJune 26, 1951 T. R. 'rHoREN .ET Al. 2,558,161

VALVE ASSEMBLY Filed Dec. 21, 1945 2 Sheets-Sheet 2 Patented June 26,1951 UNITED vllvl ASSEMBLY Theodore hilfen, Clefeliid; ;i1..ilisAspelin`, eleve`laiia Heights, ohio, assignirs to ThoniiisoiiProilh'ots, lne., cleveland, ohio, a

corporation "of 'O'li' supporting bearing to better hold the valveagainst cooking. The interior 'of the heine or hollow hee-d Jof therelief 'valve carries hexihie sheet material such 'as 'rubber forclosing aber'- tures in the relief 'valve head, but adapted to' heuelie'ote-d from the apertures to loi/:hess huid through the valve headeven When the riin of the valve is seated.

The invention will hereinafter be speeilie'ally described as 'embodiedin an aircraft yfuel bump,

but it should beunderstoori that the vvalveA tous struetiorls of thisinveritiori are hot li'iiiit lto such llsaee since theyare adapted frgen] al lisa'ge in the reflief of' l'id bres'sl'lre and in 'theby=passirlg of fluid.

Aircraft fuel systeins' breferablyhave rfuel pumps arranged ih series or'tender toirisuie ilelivery of fuel to the engine eveii thel ehl'it of'failure of one 'of the purhps. Ih siren systrlis the pumps are equippedwith loyfpess valv sto -pe'riiiit passage o'i fuel through theii'iope'rative Pump@ Further, in such aircraft l'lel s ys i.'el r 1s;it* is desirable t riair'ltaiil a; Constant f li prSSli the e'arbur'eterof the airplane en e bas anbientair pressure or suercharger bre ure suchas eiiists in the intake inaniold of the ehi gine. Since the purip's maydeliver fluctuating' pressures, a relif valve rnechanisr is provided`which will vent exee's's pressures back? t the ii'if' take side of thepump. The reliefr valve is 'set te maintain any Vdesired pum'p pressure:ad` instable spring load on the relief valve' is prei vided for thispurpose'. A Vc'iii'tpllra'iglli arrange-i ment is also provided to beslil'oje'ctell te lli'il' discharge pressure on one side thereof andambient air or superharge'r pressure o'ii the other side thereof. Thisoia'phrgiii lrriihe# nient automatically cmijensates'- for uetllationsin the air and fuel pressures s o that the dis; Charge pressure' Of thpump is Ctill'd tirely by the adjustable springV nealis.

Iii accordance with this ilu'ferition',y eoiiibied relief valve andhyrpass valves are ilrovi'ded wherein the rel-lef valve has a dn'ie orhollow head portion to whichv is attached an elongated increasing theoverall Sursee goed. Seating 9f..lh.va1ve .1.11 ddii'nlih-l9llew 6r5911i@ relief valve; aooordiiig to a. .deiQrmable Joy.. Cari t'ekh ef1.1. 'Qmpsedl .fph mini' j f hregrihteu faerie; eribie ii astioiiiaterlel, 'or like. The he.ad...or. deine. whe relief ,relif isapertura; ehu thfe'se fp' faire eioseilbif `the were@ ive-1v@ chargesitieof the isti aco'ri'iloiried i'lii and byilass vali as whereinholle-iii hil ertu' il relief v'lf receives; in thehell'bw ad thereof;deforl'l'l islet-miss valve toiitrollihe lieti thro'iieii theapertlires.

A still further object 5i this i` provide a ooriihliietirelief aridhyjpumps ehu the like' the relief if" e hollow head ahh et iliie 'ing'long"'efl euiiie holii the valve gailist ooo'llilg ao shereiii thehollow head of th e valve receives by-pass cn' trol mearis; withoutiiiereasiiie the overall height of theass'embly. n

Another obiert of the intritioii is to' provide e relief valve withg'iiiiie steril that projette oh both sides of thesatiiig feooff teilteto ford increased hearing suiiiiort for lthe talee Without increasingthe overall height of -th as: sehitly.-

A further -obleot ortlie iii-veiitiori is to' eroi/ ille e relief valle-ivitii flexible .urethra-giri type hy: pass control.

A still further object of the invention is' 'to pio- A still furtherobject of the invention is to provide a combined relief and by-passvalve including an apertured relief valve head with a seating facetherearound and a diaphragm type spring pressed by-pass valvecontrolling flow through the apertures in the relief valve.

Other and further objects of this invention will be apparent to thoseskilled in the art fromthe following detailed description of the annexedsheets of drawings which, by way of preferred examples only, illustratethree embodiments of the invention.

On the drawings:

Figure 1 is a vertical cross-sectional view taken through an aircraftfuel pump equipped with a combined relief and by-pass valve according tothis invention.

Figure 2 is an enlarged fragmentary vertical cross-sectional Viewfurther pump and valve of Figure 1.

Figure 3 is a fragmentary vertical cross-sectional View illustrating themanner in which uid flow is by-passed through the relief valve ofFigures 1 and 2. Figure 4 is a view similar to Figure 3 illustrating asecond embodiment of a combined relief and by-pass valve according tothis invention.

" Figure 5 is a View similar to Figure 3 illustrating a third embodimentof aV combined relief and by-pass valve according to this invention.Figure 6 isa transverse horizontal cross-sec- 'tional view takensubstantially along the line VI-VI of Figure 5.

`As shown on the drawings: A Y In Figure 1 the reference numeral IBdesignates generally an'aircraft fuel pump including an open topped pumpcasing II, an open ended valve casing I2, and an open bottomed springcasing I3, all held togetherr in superimposed rela- .tion by means ofbolts or studs I4.

The pump casing I I has an internally threaded .boss I5 at one endthereof communicating with an inlet chamber I6 in the casing. A secondinternally threaded boss I1 is provided at the other end of the casingII and communicates with a pump discharge chamber I 8 in thecasing.

A sleeve I3 is pressed Yin the casing II between the inlet chamber I6and discharge chamber I8 and defines, with its innersurface, a pumpingchamber communicating at 20o: with the inlet chamber I6 and at Zlib withthe discharge chamber I8.

A pump rotor 2| is eccentrically mounted for rotation Within the sleeveI3 and has sliding vanes 22 cooperating with the inner surface of thesleeve to pump material from the inlet chamber I6 through the apertureor port 20a and through the aperture or port- 20D into the outletchamber I8. Y l 1 4 The valve casing I2 has an open topped inlet chamber23 communicating through a port 24 with a passageway 25 joined with theinlet chamberIB of thecasingII.

A central lopen-ended chamber 26 of smaller illustrating the diameterthan the chamber 23 is provided in the casing I2. This chamber 26 issurrounded at its upper open end by a valve seat 21. A port 2B joins thechamber 26 with a passageway 29 opening into the discharge chamber I8 ofthe casing II.

The casing I2 carries a tubular bearing or guide 36 in the center of thechamber 26. This guide projects through the open top of the chamber 26into the central portion of the chamber 23, for a purpose to behereinafter more fully described.

The casing I3 is in the form of an inverted cup with an outturned flangel3a around the bottom open end thereof receiving the bolts or studs I4therethrough. A flexible diaphragm 3I composed of syntheticrubber-impregnated fabric or similar sheet material is clamped aroundits periphery between the outturned flange 13a of the casing I3 and thetop of the casing I2. The diaphragm 3I separates the chamber 23 of thecasing I2 from a chamber 32 in the casing I3.

A rod 33 extends through the center of the diaphragm 3l from the chamber32 into the tubular stem guide 3D in the chamber 26. A washer o1' flangeproviding member 34 underlies the central portion of the diaphragm 3Iand is axed to the rod 33 as by means of brazing, welding or the like.'

A spring retainer 35 overlies the central portion of the diaphragm 3| inthe chamber 32 and has a central collar portion 35a, receiving a neckportion 3h11r of the diaphragm therethrough to sealingly clamp thecentral portion of the diaphragm to the rod 33 and to cooperate with thewelded bond holding the washer 34 on the rod for compelling comovementof the diaphragm with the rod.

The upper end of the rod is slidably guided in a hollow post 36depending from the top of the casing I3. This post 36 has a shoulder36a. engaging the underface of the top Wall of the casing I3 and athreaded portion 36h projecting through an aperture in the top Wall ofthe casing. A nut 31 is threaded on the threaded portion 36h andoverlies the top wall of the casing to hold the post 36 in the chamber32 in spaced relation above the diaphragm 3| and retainer 35. Ascrewdriver slot 36o is provided in the free end of the post portion 36hso that the post can be rotated. The depending portion of the post inthe chamber 32 is externally threaded as at 36d and receives, inthreaded relation therearound, an upper spring. retainer 38. The springretainer has an outturned peripheral ange which is notched to receivetherein ribs I3b along the side wall of the casing I3. The retainer 38is therefore held against rotation relative to the casing I3 but canslide up and down in the chamber 32 of the casing when the post 36 isrotated. A coil spring 39 is compressed between the retainers 35 and 38in the chamber 32 and thus acts on the diaphragm 3| and post 33 to urgethe same toward the chamber 23 of the casing I2.

A combined relief and by-pass valve assembly 40 controls flow around thepumping element of the pump I0 to relieve excess pressure from thedischarge chamber I8 of the pump back to the inlet chamber I6 and toby-pass fluid from the inlet chamber I6 around the pumping element tothe discharge chamber I8.

The valve assembly 40, best shown in Figures 2 and 3, is composed of arelief valve having a hollow domed head 4I with a rounded rim portion 4Ict for seating on the seat 21. A hollow stem 42 assainir is welded,braced, yor otherwise .ani-sed tothe apex of the .head 4| and dependsaround Aa centr-a1 aperture 44|b in thaip'ex 'Gf the head; The Stem 42is slidably seated in the stem 'guide .30 and has Ya vrounded closed.bottom 42a. The rod 33 projects freely through the aperture 4Ib` in thevalve head '4I into th'ehollowstem 42 vand is seated on the bottomrvizaof the stem. Since the :rod 33 is loaded by the spring 39, 'the roundedbottom end 33a of the rod acts on lth'e rounded bottom 42a of the stem42 for urging 2the:seating face I41a of the valve head 42| against theseat 2-1. `Since the head 4 I of the relief valve hollow anddom'ed toprovide lan apex above the V"seating face 43Ia, the stem-guide .'33 Acanproject into theihead of the Valve and have an ihieased bearing llengthfor the 'stem 42 without increasing the overall height of the assembly.Because of this arrangement, the relief valve is better guided for-straight axial movement to Ahold `the valve head 4| against coeli-v-ing. -In addition, the rod 33 facts on the very bottom of the -v'alvenstein 42 and the Y'pressure of the spring 39 is applied tothe reliefvalve ata level 4rriaterfially below the seating face 4 Ia of the valve.This arrangement further minimizes possible cooking of the valve head4I. 'The -rod 33 'is spaced from the valve head 4I and hollow stein 42and its rounded Tend 33acan rook on the rounded bottom 42a of the stemto accomodate cooking movement of the `rod without imparting 'suchmovement to the valve head 4I.

The valve head 4I is a'pertured between the seating face 4Ia and 'the-eentral Vaperti-ire 4Ib in the apex of the head as at .4I`c toaccommodate byepassing of fluid from the chamber v23 into the chamber 26even when the'uvalv seating face -4Ia is seated on the seat 2l. Toeontrol the by-'pas'sing of fluid through the apertures 4Ic of the valvehead 4I, a defcarinabl'e diaphragmetype lley-pass valve 4is provided.This valve `intzludes a.- diaphrag'm Sheet 43 l-inin'g the 'interior ofthe relief valve head 4I. The :sheet -43 ean be Ycomposed of flexible'or limp impervious |material such as synthetic rubber-impregnatedfabric, synthetic rub ber sheet material, deformable plastic sheetmaterial or the like. The diaphragm 43 is molded or deformed to closelyhug the under isurface of the relief vali/e141 and to Surroundthe-stem-42 at the 'apex of the head 42|.. Thus the diaphragm 43 has acentral aperture f43a 'receiving the valve stem 42 therethrough togetherwith a depending rim portion 43h for Aseating on -the inner surface ofthe rounded rim 4Ia, of the kvalve head 4I.

A Iradially `deformable spring 44 holds the -dia phragm 43 in sealingrelation with the 'valve head 4I to close 'the aperture 4Io. spring 44has an apertured central portion 44a 'seated around the apex end of .thevalve stemf42 :andheld against the valve head 4I by a feoil spring 45which surrounds the stem guide 3l] and is bottomed on vthe top of thepump 4easing I'I A plurality of spring lingers 44o radiate 'from the`vcentral portion l441i and are contoured to `hug the under surface ofthe diaphragm 43 for holding the Evdiaphrag'In -inlseal-A ing relationwith the `valve head 4|. These `fingers 44h are adapted to be 1deflectedradially or inwardly whenever pressure in the apertures 4Ie of the valvehead 4I eiceeds, predetermined differential above .the pressure `on theunderfaee of the diaphragm. In addition to yd'e'heotion of the springngers 44o, the 'coil spring 45 can vbe compressed to permit the centralportion 44a of the spring and the central portion of the diaii phragm 43to move away from the valve head. The :apertures 4Ic ofthe valve head4lwillth'en accommodate .duid 'now Jfrom the chamber 23 into the chamber'2.6, even though the valve head is seated on its 'seat 211..

In operation of the pump ID, the spring chamber .32 is vented to ambientair pressure or to intake manifold pressureof :the aircraft 'engineandthe spring 33 in this chamber is loaded vto' exert a predetermined:load son the relief valve for urging the valve toward closed position.The pump is operated and the discharge pressure vof the pump in thechamber |18 will exceed the intake pressure .inthe chamber I6. .When thedischarge pressure exceeds :a Ipredetermined 'dife ferential overambient air or intake manifold pressure, the relief valve will open torelieve lexcess pressure back to the inlet vside 'of the pump. Thus',the valve head 4I will be unseated from 'theseat 21 and fluid willirlowfrom the 'disch-arge chamber I8 through the passageway 29, port 28,chamber i6, into chamber 23, 'and thence through port 24 and passageway25 into the inlet chamber I6. However, when pressure in .th'e discharge`chamber I3 is .less than pressure in the vinlet chamber I6 by apredetermined differential, the springs `44 and 45 will be 'deflected touncover the' apertures 4Ic in the valve head 4I `and permit reversefluid flow from the inlet chamber I6 to the discharge chamber |8. In theembodiment of Figure 4, parts identical with parts described inconnection with Figures l to 3 have been identified with the samereference numerals. As shown in Figure 4, the kspring 39 is bottomed .ina retainer 50 having a dimple 58o in the central portion thereof. .Awasher 5I is 'seated on the vcentral portion of a diaphragm 52separating the chambers 23 `and 32 and clamped between the casing partsI2 and I3 as described hereinabove. The washer 5I has a .raised convex.portion 51o .projecting into the dimple 5&0. and rockably supportingthe spring retainer 5B so that cooking movements of the retainer 5e arenot imparted tothe washer 5l.

f A valve stem 53 slidably .seated in .the guide 33 has a rounded upperend 53a deecting the vcentral portion 52a of the diaphragm into 'theconvex portion 5I'a of the washer 5I and thereby centering the washer onthe diaphragm. .In this embodiment, therefore,the diaphragm is notcentrally apertured but is locally deflectedv and is seated between thewasher 5I and the stem` 53.

A combined relief and by-pass valve assembly 54 is provided forcontrolling 'ow between the chambers 23 and 25 for the same purpose de.-scribed hereinabove. This assembly includes a valve head 55 with a hattop wall 55a underlying the diaphragm 52 and 'receiving the 'stem 53through the central portion thereof. The top 55a is secured to the stem53 as :by welding, brazing or the like. The central portion of thediaphragm 52 is thus clamped between the vtop Wall 55a of the Valve headand the Washer 5I.

rThe valve head has a depending side wall or skirt 55o extendingdownwardly from the `top wall 55 thereof and terminating yin a beadedrim 55o seating on the valve seat 21. The Side wall 55o is apertured asat 55d to provide for the by'- passing of huid through the Valve.

A diaphragm-type bye-pass valve is provided for controlling now throughthe apertures 55d. This 'diaphragm byepass valve is composed vof arubber skirt or sheet 55 lining the inside .surface of the valve head 55and centrally apertured to receive the valve stem 53 therethrough. Theskirt '5t preferably has a bead 'or an'ge 55d around the aperture..therein. Y 1

7 The stem guide 30, as in the modification described in Figures 1 to 3,projects into the chamber 23 and does not interfere with the seating ofthe valve head 55 because the head is hollovvand its top wall is spacedfrom the top edge of the guide. The top end of the guide is providedwith a shoulder 30a receiving a spring 5l for holding the by-pass valveskirt 56 against the valve head 55. This spring includes a centrallyapertured portion 51a. seated on the guide 3S. Fingers 5112 extendupwardly from the portion v57a to underlie the top portion of the skirt56 vand to engage the flange orbead 55a, for sealingly clamping theskirt to the stem 53. A plurality of spring ngers 51o depend from thespring portion 57a and act against the lower portion of the skirt 55 tohold the skirt against the side wall `55h of the valve head 55 forsealing the apertures 55d.

"The'dome or high hollow head of the valve assembly :3, like the domedvalve head 4I, accommodates increased bearing length for the stem guide3B without increasing the overall height of the assembly so that thevalve stem 53 isv better held against cooking to maintain tin valve head55 in position for eicient seating on the seat 21. When intake pressureexceeds discharge pressure by a predetermined differential, the springiingers 57o will be deflected to allow the rubber by-pass valve skirt 5tto move away from the apertures 55d thereby permitting iiuid flowthrough the valve head 55.

In the modication shown in Figures 5 and 6, parts identical with partsdescribed in connection with Figure 4 have been marked with the samereference numerals.

As shown in Figures 5 and 6, the spring 39 is bottomed on a retainer iinwith a depressed central portion 60a providing a rounded projection onthe bottom of the retainer. A washer 6I overlies'the central portion ofthe diaphragm 62 and has a depressed central dimple B la. rockablyreceiving the projection 66a of the retainer therein.

A valve stern $3 is slidably mounted in the guide 3G and has a roundeddepressed upper end 63a. The central portion of the diaphragm E2 isdepressed by the portion Bia of the washer 6| into the recessed top Wall63a of the stem 63. In this arrangement, therefore, the washer Si iscentered on the diaphragm by providing a projection thereon whichdeforms the central portion of the diaphragm as at 62a into a recess 83ain the upper end of the valve stem 83. The spring retainer 63 can rockin the dimple provided by the projection tia of the washer 6l withoutimparting rocking movements to the diaphragm,` or washer.

A combined relief and by-pass valve assembly 64 is provided for thepurpose described hereinabove. This assembly includes a relief valvehead 65 with a iiat top wall 65a underlying the central portion of thediaphragm 62 and having a central aperture bounded by a depending collar65h receiving the valve stem 63 therethrough and f secured to the valvestem as by welding, brazing or the like. The collar 55h has an outturnedflange 65o at its lower end.

The valve head 65 has a side wall or skirt 65d and a rounded rim end 65eproviding a seating face for the valve. The side wall 65d has aperturesE5f therethrough spaced at intervals therearound adjacent the rim end55e.

, A diaphragm type by-pass valve is provided for lining the Valve head65. This valve is composed of a rubber sheet or skirt 66 with a centralaperture surrounded by a bead 66a seated in the recess around the collar65h and bottomed on the iiange 65o of the valve head. The bead 66asnugly ts in the recess in sealing engagement with the valve head.

The skirt 66 has a plurality of flapper segments 65h lining the sidewall 65a of the valve head. As shown in Figure 6, these segments 66h areso positioned as to cover the apertures 65j in the side wall of thevalve head.

A spring member 61 is mounted in the diaphragm 66 and includes anaperture top wall portion 61a surrounding the bead 66a of the diaphragmand cooperating to hold the bead in the recess afforded by the collar65h and the ange 65e. A plurality of spring fingers 61h depend from thetop wall portion 61a to act on the iappers 66h of the diaphragm forholding the fiappers in sealing relation with the apertures 65j. Thefingers 61h are adapted to be deiiected to permit the flappers 66h touncover the apertures 65j and accommodate iiow of fluid from the chamber23 to the chamber 26 even when the valve head 65 is seated on the seat21. As in the other embodiments, the stem guide 30 projects into thehollow head of the valve to have an increased bearing length for thestem without increasing the overall height of the assembly.

From the above descriptions it will be clear that the invention providescompact combined valve assemblies controlling flow of fluids in oppositedirections with one of the valves having a hollow head or domeaccommodating therein a stem bearing guide and with the other of thevalves controlling flow through the head of the rst valve by means ofspring pressed diaphragm skirts.

It will, of course, be understood that various details of constructionmay be varied through a wide range without departing from the principlesof this invention and it is, therefore, not the purpose to limit thepatent granted hereon otherwise than necessitated by the scope of theappended claims.

We claim as our invention:

1. A combination relief and by-pass valve assembly which comprises arigid relief valve head having a hollow dome with a seating facetherearound, a valve stem depending from the apex of the dome of saidhead, a valve stem guide slidably supporting said stem and projectinginto the head beyond the seating face of the head, said head havingapertures therein, a flexible liner in said head covering saidapertures, and deflectable spring means yieldngly holding the lineragainst the head to seal the apertures.

2. A combination two-way fluid flow control valve assembly comprising arst valve member having a hollow dome head and a central depending stem,said valve head having a seating face therearound intermediate the endsof the stem, a stem guide slidably kreceiving said stem and projectinginto said head beyond the seating face thereof into spaced relation fromthe apex of the head, said head having a passage therethrough, a secondvalve in said head controlling flow through said passage, said secondValve including an irnpervious flexible liner in the head, conforming tothe contour of said head, a plurality of arcuate spring ingers urgingthe liner into sealing engagement with the head, and said second valvebeing movable with the rst valve and deflectable away from `the valvehead to open the passageway.

3. A combined by-pass and relief valve com- 9 prisingv a hollow domedrelief valve head having a seating face therearound, said head havingpassageways therethrough, a flexible diaphragm type ley-pass valvelining said head for sealing said passageways, and bowed spring fingersmounted in said head and acting on said diaphragm to urge the diaphragminto sealing relation with the head.

4. A combined by-.pass and relief valve which comprises a relief valvehead member having a seating face therearound and apertures there.-4through, a hollow closed' bottomed open topped stem secured to therelief valve member and depending therefrom, a spring-pressed rodprojecting freely through the relief valve member into the hollow stemand seated on the bottom of the stem, and a spring-pressed diaphragmliner on said relief valve member controlling fluid' flow through theapertures therein.

` 5'. A combined relief` and by-pass valve assembly for pumps and thelike which comprises a domed head having a seating face therearoundspaced axially from the apex of the dome, said head having an aperturethrough the apex thereof and additional apertures therearound betweenthe seating face and the apex, a hollow open-topped closed-bottomed stemsecured to the head around the aperture in the apex thereof anddepending through the head into. spaced axial relation beneath theyseating face of. the head,y a spring-pressed rod projecting freelythrough the aperture in the apex of the head into the hol- W Stem andbottomed the bottom of the stem for urging the valve seating face intoclosed position, flexible impervious material lining the head forclosing the apertures between the aperture in the apex and the seatingface o f the head, and yieldable spring means holding said liner insealing relation with said head to closeL the apertures.

6. A combined relief and by-Vpass valve assembly comprising a reliefvalve head having a depending skirt therearound with a rim end providinga valve seating face, saidskirt having apertures therein, a stem securedto the top of the' head and depending therefrom beneath the rim end ofthe skirt, guide means slidably supporting said stem and projecting intothe skirt of the head in spaced relation therefrom for increasing theguide length to hold the head against cocking without increasing theoverall height of the assembly, and spring-pressed means in the headacting on the skirt to seal the apertures, said means including adeectable diaphragm lining said skirt and elongated fiat springs urgingsaid diaphragm radially outwardly against said skirt, said diaphragmbeing adapted to be deflected from the skirt for accommodating iuid flowthrough the apertures of the head.

'7. A combined relief and by-pass valve assembly comprising a reliefvalve member having an apertured depending skirt with a rim endaffording a seating face, flexible material lining said head to coverthe apertures in the skirt, and yieldable spring means in extendedsurface engagement with the inner surface of said iiexble materialdirectly urging said lining against said skirt to yieldably hold thesame in sealing engagement with the skirt.

8. A combined relief and by-pass valve assenjrbly comprising a reliefvalve head having a depending skirt with a rim end providing a seatingface for the relief valve, a stem depending from the top wall of thehead in xed relation to the head, a stem guide slidably supporting saidstem and projecting into the head to increase thev bearing support forthe stem without increasing the overall height of the assembly, aflexible liner in said head abutting the inner surfaces of said skirt,and arcuate elon- ,gated springs seated on said guide to directly abutsaid liner, said skirt of the head vhaving apertures therethroughcovered by said liner and said spring means being arcuately defiectableto yi'eldably hold the liner for sealing the apertures and for recedingfrom the skirt to accommodate fluid' flow through the apertures.

9. A combined relief and by-pass valve assembly comprising a hollowrelief valve head having apertures therein,r flexible iiapper members insaid head closing said apertures, flexible flat spr-ings in flatwisecontact with said flapper members to urge said members against saidvalve head, and guide means slidably mounting said head. f

10. A combined relief and by-pass valve assembly comprising a rigidvalve head having atop Wal-l and a depending skirt therearound with arim end providing a seating face, said skirt having*l aperturestherethrough, a liner in said head having flapper segments acting on theskirt to close said aperturearand aspring member carried by the top wallof the head having deflectable fingers acting on said flappers toyieldably urge the same into sealing relation with the skirt forYsealing the apertures.

11. A combined relief and by-pass valve assembly lfor pumpsv and thelikefwhich comprises a spring-pressed diaphragm, a rod extending throughsaid diaphragm and having a flange-delining member thereon underlyingthe diaphragm, a relief valve having a hollow guide st em receiving saidrod freelyftherethrough and seating the rod on the bottom of the stem,said relief valve having a domed head secured to said stem and providinga seating face around the stem intermediate the ends thereof, a sternguide slidably receiving the stem and projecting into the domed head,impervious sheet material lining said domed head, a radially deectablespring underlying the sheet material to urge the'sheet material intosealing engagement `with the domed head, a coil spring surrounding thestem guide acting on said radially deformable spring to urge the springagainst the top of the domed head, and said domed head having aperturestherethrough accommodating fluid ow when the coil spring and theradially deformable spring permit movement of the liner away from. thehead to uncover the apertures.

12. A combined relief and by-pass valve assembly for pumps and the likecomprising a springurged diaphragm, a relief valve head having a flattop wall underlying said diaphragm, a valve stem projecting through saidfiat top wall and having a rounded upper end depressing the diaphragmaway from the top wall of the head, a washer member having a recessreceiving the deformed portion of the diaphragm and confining thediaphragm portion between the stem and the washer, a spring retainerrockably mounted on the washer, said top wall of the head having adepending apertured skirt portion with a rim bottom providing a valveseating face, and spring-pressed ilexible lining material in said valvehead sealing said apertures and adapted to be radially deflected fromthe valve head for bypassing fluid through the relief valve.

13. A combined by-pass and relief valve assembly for pumps and the likewhich comprises a relief valve head having a central recess in the topthereof and a stem depending therefrom, a diaphragm overlying the top ofsaid head, means having a projection thereon overlying the diaphragm anddeforming a portion of the diaphragm into the recess, said valve headhaving an apertured side wall, and a spring-pressed liner in said headclosing the apertures in said side wall and adapted to be deflectedradially away from the side wall to by-pass fluid through the head.

14. A valve assembly comprising a valve seat, a stem guide extendingthrough said seat, a valve having a head with a seating facetherearound, and a stem extending into and depending from said head toextend on both sides of a transverse plane through said seating face,said stem guide `slidably receiving said stem and having increasedbearing engagement therewith due to the extension of the guide throughthe valve seat and the extension of the stem into the valve head beyonda transverse plane through the seating face.

15.u A valve assembly comprising a relief valve head having a hollowdome with a seating face therearound, a valve stem depending from theapex of the dome of said head, a valve seat accommodating said seatingface, and a valve stem guide extending through said seat slidablysupporting said stem and projecting into the dome of said lhead beyondthe seating face of the head When said seating face is seated on thevalve seat.

16. A valve assembly comprising a rigid valve head having a peripheralseating face and a central depending stem, said valve head having arecess therein surrounding the valve stem and adapted to accommodate avalve stem guide freely therein, said head having apertures therethroughcommunicating with said recess between the peripheral seating facethereof and the valve stem,` and a flexible liner for said .valve headseated in said recess and disposed around the valve stem, said linerfollowing the contour of said recess and adapted to seal the aperturesin the valve head when pressure in the recess is greater than pressuresurrounding the outer face of the valve head and adapted to be deectedradially inwardly away from the valve head to uncover the apertures inthe valve head and accom-modate fluid flow passage through the valvehead when the pressure on the outer face of the valve head is greaterthan the pressure in the recess.

17. In a combined relief and by-pass valve for a fluid pump including acasing having a first chamber for connection to the intake side of thepump and a second chamber for connection to the discharge side of thepump, the improvement which comprises means in said casing defining avalve seat between said chambers, a valve head having an apertureddependent skirt dening a peripheral seating face for engagement withsaid valve seat, means guiding said valve head for axial openingmovement to relieve excessive discharge pressure in said chamber, adeflectable lining for said skirt, and dellectable spring fingersnormally urging said lining against said skirt to close said skirtapertures while allowing by-passing of fluid from said rst chamberthrough said skirt apertures against the action of said spring lingersinto said second chamber.

I THEODORE R. THOREN.

LESLIE L. ASPELIN.

REFERENCES CITED The following references are of record in the iile ofthis patent:

UNITED STATES PATENTS

